Connector for interconnecting conduits

ABSTRACT

A connector for interconnecting two open-ended, generally aligned conduits comprises a sealing unit movably connected to a toggle mechanism. The connector is lowered by a simple tool between the conduit ends until yokes of the toggle mechanism move inwardly to engage the flanges of the conduit ends to align further the conduits. Clamps interconnected by tension rods pivot downwardly to clamp the conduit ends against the sealing unit. Tubular seals within the sealing unit are then moved outwardly to engage with the conduit ends by further toggle arrangements actuated by downward movement of a bar.

BACKGROUND OF THE INVENTION

The present invention relates to connectors for interconnecting conduitsand in particular, though not exclusively, to connectors forinterconnecting conduits, such as pipe for carrying for example oiland/or gas, in subsea locations involving the connection of conduits ata subsea installation.

In one such situation, it is necessary to connect conduits located atthe subsea installation to conduits which extend above sea level inorder to provide a flow line from the installation. A sea-going vesseltows the open end of a conduit extending to above sea level into thevicinity of the open end of another conduit extending from the subseainstallation. The two conduit ends are then roughly aligned andinterconnected by a suitable connector in a sealing manner.

One known type of connector for interconnecting the conduit endsconsists of an annular seal and clamp which are carried by aninstallation tool to the generally aligned conduit ends. Theinstallation tool is then required, in successive operations: to engagewith each conduit and align the conduit ends; to lower the seal betweenthe conduit ends; to move one or both conduit ends towards the seal; toactuate the clamp to effect clamping of the two conduit ends against theseal; and then to disengage from the conduits for retrieval of theinstallation tool. Thus, in order to complete the interconnection of theconduit ends, five successive operations have to be carried out and theinstallation tool is required to perform three main tasks whichnecessitates the use of highly complex and expensive machinery toachieve the task manoeuvres. Furthermore, because the operations arecarried out successively the whole installation procedure takes sometime to complete, thereby further adding to the cost.

In another known type of connector, a telescopic sealing unit containingtubular seals slidable by a worm and wheel mechanism, is lowered by aninstallation tool between the generally aligned conduit ends with theunit also engaging around the conduit ends. Precise alignment of theconduit ends is achieved by friction clamping. The installation tool isthen required to actuate the worm and wheel mechanism to slide the sealsoutwardly into sealing engagement with the conduit ends. The tool isthen retrieved. Thus, although this procedure is less complex than theaforementioned procedure, there are still three successive operations tobe carried out and the installation tool is still required to performone main task, namely actuation of the worm and wheel mechanism.Furthermore, large locking forces are experienced by the sealsthemselves, which creates the possibility of damage.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide aconnector for interconnecting conduits which is capable of beinginstalled by a much simpler and quicker procedure than has been achievedheretofore and without the use of a complex and costly installationtool.

According to the present invention, there is provided a connector forinterconnecting two generally aligned open-ended conduits, the connectorcomprising means for providing a seal between the conduits ends, andbeing characterized in that it includes a toggle mechanism, connected tothe sealing means, for moving the conduit ends further into alignmentwith each other and for clamping them against the sealing means locatedtherebetween.

The toggle mechanism preferably comprises means for engaging withflanges provided on the conduit ends and clamping means movablyconnected to the flange engaging means by toggle arrangements, such thatactuation of the toggle arrangements moves the engaging means intoengagement with the flanges and causes the clamping means to clamp theconduit ends against the sealing means. The flange engaging means arepreferably slidably connected to the sealing means.

In one embodiment, the clamping means comprises two clamping membersinterconnected by tension rods, and the flange engaging means comprisestwo yokes located between the clamping members and each movablyconnected to a respective one of the clamping members by a separatetoggle arrangement. Each toggle arrangement preferably comprises atleast one lever pivotally connected at its ends to the yoke and to theclamping member, respectively.

The sealing means preferably comprises a housing having a generallycylindrical chamber extending therethrough and containing at least twotubular seals, and a further mechanism operable from outside of thehousing for moving the seals into sealing engagement with the twoconduit ends when the sealing means is located therebetween. In apreferred embodiment, the seal moving mechanism comprises at least onefurther toggle arrangement located on the outside of said housing. Theseals may be connected to carriers located within the housing andslidable relative to the housing by operation of the seal movingmechanism. Each further toggle arrangement may consist of two leverspivotally interconnected at their adjacent ends and pivotally connectedat their other ends respectively to connecting members extending throughapertures in said housing wall and being connected to the seal carriers.

In alternative embodiments, the sealing means may comprise a valvearrangement, such as an emergency shutdown valve, or other pipe-lineequipment.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be further described by way of example withreference to the accompanying drawings, in which:

FIG. 1 shows a side View of a connector, in accordance with oneembodiment of the invention, with the connector shown in an "open"position;

FIG. 2 shows the same view as in FIG. 1, but with the connector in a"closed" position;

FIG. 3 shows a horizontal sectional view of the connector in a "closed"position;

FIG. 4 shows an end view of the connector in an "open" position;

FIG. 5 shows an end view of the connector in a "closed" position;

FIG. 6 shows a vertical sectional view of the connector in an "open"position;

FIG. 7 shows an enlarged horizontal sectional view of the sealing unitof the connector in an "open" position;

FIG. 8 shows an enlarged horizontal sectional view of the sealing unitof the connector in a "closed" position; and

FIG. 9 shows a schematic horizontal sectional view of another embodimentof the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGS. 1 to 8 of the drawings, a connector showngenerally at 1 is used to interconnect two conduits 2,3, one of which isconnected, for example, to a subsea pipe installation (not shown) andthe other of which extends, for example, above sea level. Open ends 4,5of the conduits each have outer surfaces 6,7, which taper outwardlytowards the open ends and which terminate in an outwardly-extendingflange 8,9 extending around the periphery of the conduit end. End faces10,11 of the conduits are each formed with an annular groove 12,13 andnarrow annular recesses 14,15 are formed around the internal peripheriesof the conduit ends.

The connector 1 comprises a sealing unit 16 movably connected to atoggle mechanism 17. The toggle mechanism includes two clamps 18,19interconnected by six tension rods 20. Yokes 21,22 having recesses 21a,22a respectively are located between the clamps and are connected to arespective one of the clamps by two toggle arrangements. Each togglearrangement consists of four levers 23 each pivotally connected at oneend to one of the clamps an pivot points 24 and at their other end toone of the yokes at pivot points 25. Each yoke 21,22 is slidablyconnected to the sealing unit 16 by two interconnecting members 26 whichslide in grooves 27 provided in the outer surface of housing 28 of thesealing unit 16.

The housing of the sealing unit, which is shown in detail in FIGS. 7 and8, has a cylindrical chamber 29 extending throughout its lengthcontaining two tubular seal carriers 30,31, in sealing engagement withthe inner surface of the chamber 29 by means of a series of smallannular sealing rings 32, and three tubular seals 33,34,35. By means offixings 36, the seal 33 is fixedly connected to the seal carrier 30 andthe seals 34 and 35 are fixedly connected to the seal carrier 31.Additionally, inner end 37 of the seal carrier 30 sealingly and slidablyengages with the outer surface of the tubular seal 34. The outer endfaces of the seal carriers 30,31 are formed with peripheraloutwardly-extending flanges 45 and the seals 33 and 35 protrude slightlybeyond the end faces of the seal carriers 30 and 31, respectively.

Two toggle arrangements 38 are mounted on the external sides of thehousing 28. Each toggle arrangement consists of two levers 39 pivotallyinterconnected at their adjacent ends at a central pivot 40 and at theirouter ends to two connecting members 41 respectively at pivot points 42.The two connecting members 41 extend through apertures 43 in the housingside wall and one is connected into seal carrier 30 and the other intoseal carrier 31. Grooves 44 are formed in the external side walls of thehousing 28 to accommodate the pivots 40, which are interconnected by abar 46, as shown in FIGS. 1, 2 and 6.

In order to install the connector, any suitable apparatus is first usedin order to position and retain the conduits ends, which may be in asubsea location, in general concentric alignment with each other. Theconnector to interconnect the conduit ends is then lowered by means of asimple tool so that the sealing unit is positioned between the conduitends and the yokes 21,22 are positioned over the conduits, as shown inFIG. 1. Further simultaneous lowering of the clamps 18,19 causes thelevers 23 to pivot about pivot points 24 and 25 on the clamps 18,19 andthe yokes 21,22, respectively. This pivoting action causes the yokes21,22 to slide along the tapered outer surfaces 6,7 of the conduit endsuntil recesses 21a,22a engage around the flanges 8,9 of the conduitends, thereby moving the conduit ends towards each other and intoprecise concentric alignment with each other. At the same time,connecting members 26 secured to the yokes 21,22 slide inwardly in thegrooves 27. As the lowering of the clamps 18,19 continues, anover-centring of the pivot points 24 and 25 occurs, so that pivot points24 are positioned slightly below pivot points 25, as shown in the"connector closed" position in FIG. 2. This over-centring action locksthe clamps 18,19 into a position which effects a clamping action on theyokes 21,22, thereby causing the conduit ends to be clamped against thesealing unit 16 located therebetween.

Lowering of the bar 46 pushes the pivot points 40 on the sealing unitdownwards, so that the levers 39 move outwardly, pivoting about pivotpoints 42. This moves the connecting members 41 within the apertures 43from the inner position shown in FIG. 7 to the outer position shown inFIG. 8. This movement causes the seal carriers 30 and 31 to slideoutwardly simultaneously in opposite directions with the inner end 37 ofseal carrier 30 sliding relative to the seal 34. The outer end faces ofseal carriers 30 and 31 engage with the conduit end faces, with the sealcarrier flanges 45 engaging into the annular grooves 12,13 and theprotruding portions of seals 33 and 35 engaging into the annularrecesses 14 and 15, respectively. The seals are finally locked intotheir sealing positions with the conduit ends by over-centring of thepivot points 40 and 42 such that the pivot point 40 is positionedslightly below the pivot points 42.

In order to retrieve the connector, a simple tool is connected theretowhich merely raises the bar 46, thereby releasing the togglearrangements on the sealing unit 16 to withdraw the seals from theconduit ends and subsequently lift the toggle mechanism 17 to unlock theclamps and withdraw the yokes from the conduit ends.

It can thus be seen that the connector, in accordance with the describedembodiment of the present invention, enables the conduits to beinstalled and retrieved very simply and quickly, without the need for acomplex and costly installation tool. All the tool is required to do islower and raise the clamps 18,19 and the bar 46, the aligning, clampingand sealing actions all being carried out by the connector itself.

Whilst one particular embodiment of the present invention has beendescribed, various modifications will be envisaged without departurefrom the scope of the invention, as defined in the appended claims. Forexample, the connector may be used to individually interconnect aplurality of parallel conduits contained in a bundle within a main outerconduit. In this embodiment, the sealing unit may contain furthertubular seals of smaller diameter within the seals as shown, in order toprovide the individual sealings of the interconnected conduits of thebundle.

Additionally, although the connector shown in the Figures has sixtension rods, any even number of these rods may be used depending on thesize of the connector.

Moreover, instead of using the sealing unit as shown in FIGS. 1 to 8,other sealing means between the conduit ends may be used. For example, avalve arrangement, such as an emergency shut-down valve, or otherpipeline equipment, can be utilised.

In one alternative embodiment shown schematically in FIG. 9, the sealingmeans 48 located between the conduit ends comprises a valve arrangement49. The right-hand side of this Figure shows the valve arrangementlocated between the conduits with the toggle mechanism 17 in an "open"position and the left-hand side of the Figure shows the valvearrangement installed and sealed against the conduit ends with thetoggle mechanism 17 in a "closed" position.

The connector in accordance with the present invention may be used forinterconnecting conduits in different applications such as flow-lineconnections as well as pipe-line repairs.

We claim:
 1. A connector for interconnecting two generally alignedconduits having open ends provided with flanges, said connectorcomprising:a toggle mechanism for moving the conduit ends into preciseconcentric alignment with each other, said toggle mechanism including aplurality of toggle arrangements for effecting an over-centering action,flange engaging means adapted to engage with said flanges, and clampingmeans pivotally connected to said flange engaging means by said togglearrangements; and a sealing unit for sealing between said alignedconduit ends so as to permit fluid flow through said conduits, saidsealing unit being adapted to be removably located between said conduitends and said toggle mechanism being movably mounted on said sealingunit, whereby actuation of said toggle mechanisms when said sealing unitis located between said conduit ends moves the flange engaging meansinto engagement with said flanges to align precisely said conduit endsand causes the clamping means to clamp said conduit ends against thesealing unit by said over-centering action of said toggle arrangements.2. A connector as claimed in claim 1, wherein the flange engaging meansare slidably connected to the sealing unit.
 3. A connector as claimed inclaim 1, wherein the clamping means comprises a plurality of tensionrods and two clamping members interconnected by said tension rods, andthe flange engaging means comprises two yokes located between theclamping members and each movably connected to a respective one of theclamping members by a separate one of said toggle arrangements.
 4. Aconnector as claimed in claim 3, wherein each toggle arrangementcomprises at least one lever having two ends, said lever being pivotallyconnected at said ends to one of the yokes and to one of the clampingmembers respectively.
 5. A connector as claimed in claim 1, wherein thesealing unit comprises a housing having a generally cylindrical chamberextending therethrough and containing at least two seals.
 6. A connectoras claimed in claim 1, wherein the sealing unit contains seals and theconnector also includes a seal moving mechanism operable from outside ofthe sealing unit for moving said seals into sealing engagement with theconduit ends when the sealing unit is located therebetween.
 7. Aconnector as claimed in claim 6, wherein the seal moving mechanismcomprises at least one further toggle arrangement located on the outsideof said sealing unit.
 8. A connector as claimed in claim 6, wherein thesealing unit also contains carriers, the seals being connected to saidcarriers and slidable relative to the sealing unit by operation of theseal moving mechanism.
 9. A connector as claimed in claim 8, whereinsaid sealing unit has a wall provided with apertures and connectingmembers extending through said apertures and connected to said sealcarriers, and each further toggle arrangement consists of two leverseach having first and second ends, the first ends being pivotallyinterconnected and the second ends being respectively connected to saidconnecting members extending through said apertures.
 10. A connector asclaimed in claim 1, wherein the sealing unit comprises a valvearrangement to be sealingly located between the conduit ends.